The article reviews the mechanisms of nanotoxicity, focusing on the generation of reactive oxygen species (ROS). Nanomaterials, due to their unique physical and chemical properties, can induce oxidative stress, leading to cellular dysfunction and toxicity. The overproduction of ROS can cause DNA damage, lipid peroxidation, unregulated cell signaling, and apoptosis. Critical determinants affecting ROS generation include particle size, shape, surface properties, dissolution, metal ion release, light activation, aggregation, and pH. The article highlights the importance of understanding these mechanisms for the safe development and use of nanotechnology products. It also discusses the challenges in determining the mechanisms of nanotoxicity in cells and in vivo, emphasizing the need for advanced techniques like electron spin resonance (ESR) spectroscopy. Finally, it explores perspectives on preventing nanotoxicity through dietary antioxidants and other strategies.The article reviews the mechanisms of nanotoxicity, focusing on the generation of reactive oxygen species (ROS). Nanomaterials, due to their unique physical and chemical properties, can induce oxidative stress, leading to cellular dysfunction and toxicity. The overproduction of ROS can cause DNA damage, lipid peroxidation, unregulated cell signaling, and apoptosis. Critical determinants affecting ROS generation include particle size, shape, surface properties, dissolution, metal ion release, light activation, aggregation, and pH. The article highlights the importance of understanding these mechanisms for the safe development and use of nanotechnology products. It also discusses the challenges in determining the mechanisms of nanotoxicity in cells and in vivo, emphasizing the need for advanced techniques like electron spin resonance (ESR) spectroscopy. Finally, it explores perspectives on preventing nanotoxicity through dietary antioxidants and other strategies.